Bar codes are useful for identifying and maintaining inventory for a variety of products and goods. One of the disadvantages of a bar code system is that it may be difficult to read, depending upon the available light, the environment or the angle that the bar code can be scanned. The shapes of bar codes generally need to be somewhat uniform and of course a limitation for bar codes is that they cannot be hidden out of view, but instead must be readily available so that the light from a bar code reader can impinge directly upon the bar code.
Because of some of the limitations of bar codes and bar code readers, passive transponder systems have been developed. There are for example radio frequency electrical transponders which require contact with a reader in order to be read. There are also radio frequency tag magnetic readers in which no contact is required. These magnetic RF tags can be read by a reader which activates an antenna within the RF tag when the RF tag becomes disposed within the magnetic field generated by the RF tag reader. This causes a radio frequency signal to be transmitted which can then be received by the reader.
The magnetic RF tag readers in the prior art are somewhat bulky and have an internal computer disposed therein which is dedicated to the reader itself. The disadvantages of such a reader with a dedicated internal computer is that the computer terminal is not useful for other purposes and the size of the reader makes it very awkward to use, for example it cannot be placed in a normal sized pocket or the like.